512 PISCES FISHES. 



hook into its flesh ; and, thus securing a firm hold, the lingual 

 saws, aided by the suctorial action of the mouth, tear their way to 

 its very vitals.* 



In the Lamprey the whole interior of the mouth is studded 

 with horny teeth, not merely fixed to the palate and tongue, but to 

 the cartilaginous representative of the inferior maxilla, and to the 

 inner surface of the lips. 



In the Carp tribe (Cyprinidte) the jaws are destitute of teeth, 

 but in the throat there is a singular apparatus serving for the masti- 

 cation of their food. The basilar bone at the base of the skull sup- 

 ports a broad three-sided dental plate, which might be compared to an 

 anvil ; while the two inferior pharyngeal bones are each armed with 

 four or five large teeth, so disposed, that, by working upon the 

 piece first-mentioned, they bruise and triturate the aliment before 

 it is permitted to pass into the digestive cavity. 



In Skates (Raidte) the internal surface both of the upper and 

 lower jaws are so covered with teeth, that they have the appearance 

 of a tesselated pavement : these teeth are sometimes flat and 

 smooth, so as to be merely useful in crushing prey ; but in many 

 species they are prolonged into sharp hooks adapted to prehension. 



In the Sharks a beautiful provision is met with. Several rows 

 of teeth placed one behind the other are found laid flat, and con- 

 cealed behind the jaw. One row only, composed of triangular cut- 

 ting teeth, stands erect and ready for use ; but when these fall off, 

 blunted and unfit for service, the next row rises to take their place ; 

 and thus a succession of efficient weapons are given to these terrific 

 monsters of the ocean. 



We will not enlarge further upon this portion of our subject ; 

 enough has been said for our present purpose, and the reader will 

 find elsewhere abundant information. -f- 



The teeth of osseous fishes are generally firmly anchylosed to 

 the bones ^that support them, although in a few instances they 

 are found fixed in sockets, as in the rostral teeth of the Saw-fish 

 (Pristis), and in the mouth of Sphyrfena, Acanthurus, Dicty- 

 odus, &c4 But there are other modes of attachment only met 

 with among fishes, some of which are not a little curious ; and 



X 



* Professor Owen. " ODONTOGRAPHY, or a Treatise on the Comparative Anatomy 

 of the Teeth, their physiological relations, mode of developement, and microscopic 

 structure," &c. 4to. Bailliere, 1840. 



f Vide Yarrell's British Fishes. 8vo. 2 vols. J Owen. Odontography, p. 6. 



